1. Technical Field
The present invention relates to a registration determination device, a control method and a control program therefor, and an electronic apparatus for determining whether to register a candidate image, i.e., a registration candidate of a target image, as a registered image registered in advance in order to perform image recognition of a certain target.
2. Related Art
In recent years, collation of a target image such as an image of a face included in a taken image is used in various fields. In the past, it is necessary for a user to register a target image in advance and delete a registered target image, and as a result, the user has to do cumbersome task. Accordingly, it is desired to automatically perform the registration processing and/or the delete processing.
For example, in a fingerprint collation device described in Japanese Patent Application Laid-Open No. 2000-123178 (published on Apr. 28, 2000), first, fingerprint feature data are extracted from a fingerprint feature data storage unit for each group. Subsequently, the fingerprint feature data which are input from the fingerprint image input device and of which feature is calculated are compared with the extracted fingerprint feature data, and a determination is made as to whether both of them have similar data. When there are similar data, a notification is given that registration is made to a group other than the group in question.
In a face image collation device described in Japanese Patent No. 4705512 (issued on Jun. 22, 2011), first, a registration face image and a candidate face image are stored in advance. Subsequently, when a person in question is identified based on the registration face image, the degree of similarity between three or more face images and the input face image is calculated, and when an intermediate degree of similarity which is neither the maximum nor the minimum is more than an update threshold value, the input face image is replaced with a candidate face image of which degree of similarity is the minimum.
In a face image collation device described in Japanese Patent No. 4705511 (issued on Jun. 22, 2011), first, a registration face image and a candidate face image are stored in advance. Subsequently, when a person in question is identified based on the registration face image, a mutual degree of similarity which is an average of the degrees of similarity of one candidate face images and the other candidate face images of three or more candidate face images is calculated for each of them, and a candidate face image of which mutual degree of similarity is the maximum is identified. Subsequently, when the degree of similarity of the identified candidate face image and an input image is determined to be more than a predetermined update threshold value, the candidate face image of which degree of similarity to the input face image is the minimum is replaced.
In a person identification device described in Japanese Patent No. 3564984 (issued on Jun. 18, 2004), first, registration data of an identified person is stored in advance. Subsequently, a physical feature is read, and the read physical feature and the stored registration data are compared and collated with each other, and the degree of similarity is determined. When the determined degree of similarity is equal to or more than a re-registration determination condition level which is set at the degree of similarity higher than a discrimination level for identifying a person in question, the registration data are re-registered.
In a person recognizing device described in Japanese Patent No. 4314016 (issued on May 22, 2009), first, living body information of multiple persons being recognition targets is retained in advance as registration information. Subsequently, living body information of a person being a recognition target is obtained, and the obtained living body information and each of the multiple pieces of registered retained registration information are collated with each other to obtain multiple degrees of similarity, and the person in question is recognized on the basis of the multiple obtained degrees of similarity. Subsequently, a determination is made as to whether a difference of multiple degrees of similarity among the multiple obtained degrees of similarity is equal to or more than a predetermined threshold value, and when the difference is determined to be equal to or more than the predetermined threshold value, the retained registration information is updated based on the obtained living body information.
In an individual authentication device described in Japanese Patent No. 4177629 (issued on Aug. 29, 2008), when there are input data which are determined to be another person in registered persons, individual identifying information is input, and when the degree of collation between a taken face image and face data corresponding to input individual identifying information is equal to or more than a predetermined value, face data are updated.
In an individual authentication device described in Japanese Patent Application Laid-Open No. 2004-046697 (published on Feb. 12, 2004), a registered person and a non-registered person are used to calculate a threshold value used in face authentication. More specifically, average values and standard deviation values of score values of all pairs (registered persons, non-registered persons) are calculated, and a threshold value is determined based on the values.
In a face registration device described in Japanese Patent Application Laid-Open No. 2004-302645 (published on Oct. 28, 2004), when a registration face image is confirmed as being a person in question as a result of discrimination as to whether an input face image matches any one of registration face images, times before and after this confirmation are adopted as registration times, and input face images which are input between the registration times are registered as registration face images.
However, in Japanese Patent Application Laid-Open No. 2000-123178, a new registered person similar to grouped registered persons data is not registered because this may cause false recognition. Moreover, similarity (variance) of data within the data of the person in question is not referenced, and therefore, data that allows the other person and the person in question to be easily distinguished may not be registered.
In Japanese Patent Nos. 4705512, No. 4705511, No. 3564984, No. 4314016, and No. 4177629, distance relationship between the person in question and the other person is not taken into consideration. For this reason, face image data similar to another person may be registered, and in this case, false recognition may be caused. In a case of Japanese Patent Application Laid-Open No. 2004-046697, the values are not obtained for each individual, and therefore, likelihood of being a person in question is not taken into consideration. In Japanese Patent Application Laid-Open No. 2004-302645, the data of the other person are not taken into consideration, and therefore, data which is likely to be a person in question but is not likely to be the other persons cannot be registered, and as a result, data which may be mistaken as another person may be registered.
The present invention is made in view of above problems, and it is an object of the present invention to provide a registration determination device that can appropriately register an obtained target image.